Windows only: Let's say you've put together a killer USB PC repair kit filled to the brim with antivirus, file recovery, and adware removal tools, but shortly after you plug your thumb drive into the infected machine—in the midst of your repair—your thumb drive is affected as well. Freeware portable application Thumbscrew protects your thumb drive from being written to so that your data remains safe no matter where it's plugged in. Even if you don't need it for PC repair purposes, it could still prove useful for keeping your files safe from the kids or something else along those lines. Thumbscrew is freeware, Windows only. Thumbscrew [Iron Geek via MakeUseOf]